there is another way
<div class="inputblock" style="width: 350px;"> <ajaxToolkit:AsyncFileUpload runat="server" ID="FileUP" ClientIDMode="AutoID" UploaderStyle="Modern" OnUploadedComplete="FileUP_UploadedComplete" Width="100%" /> </div>
it does something like this
<div id="ctl00_PopUpPlaceHolder_FileUP"> <input name="ctl00$PopUpPlaceHolder$FileUP$ctl00" id="ctl00_PopUpPlaceHolder_FileUP_ctl00" type="hidden"> <div id="ctl00_PopUpPlaceHolder_FileUP_ctl01" style='background: url("/WebResource.axd?d=some&pars") no-repeat 100% 1px; margin: 0px; width: 100% !important; height: 24px; text-align: right; min-width: 100%;'> <input name="ctl00$PopUpPlaceHolder$FileUP$ctl02" id="ctl00_PopUpPlaceHolder_FileUP_ctl02" style="width: 100%; font-size: 14px; opacity: 0; -moz-opacity: 0.0;" type="file"> <div style="text-align: left; margin-top: -23px;" type="text"> <input name="ctl00$PopUpPlaceHolder$FileUP$ctl04" id="ctl00_PopUpPlaceHolder_FileUP_ctl04" style="width: 248px; height: 17px; font-family: Tahoma; font-size: 12px;" type="text" readonly="readonly"> </div> </div>
and you can always change sss to change any silling as follows:
#ctl00_PopUpPlaceHolder_FileUP_ctl01 { background: url("/img/input_file.png") no-repeat right top !important;
it works.
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